<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>float</title>
    <style type="text/css">
        div div{
            border: 1px solid #f00;
            width: 80px;
            height: 60px;
            margin: 2px;
            float: left;
        }
        #include{
            border: 1px solid #00f;
            width: 256px;
            height: 194px;
        }
        #div1{height: 80px;}
    </style>
</head>
<body>
<div  id="include">
    <div id="div1">块1</div>
    <div id="div2">块2</div>
    <div id="div3">块3</div>
</div>
</body>
</html>